Some integrated circuit (IC) devices have input buffers to convert analog data input signals into full-rail complementary metal-oxide-semiconductor (CMOS) signals. For single-ended input signals, the transition from a logic ‘high’ to a logic ‘low’ is dependent on when the input signal crosses a reference voltage. A differential amplifier may detect such a transition.
A metal-oxide-semiconductor (MOS)-based self-biased differential amplifier can convert input signal swings to full-rail signals. However, as the supply voltage becomes very low, there may not be enough voltage margin to keep the input buffer components within a specified operating region. Some other input buffers that can operate at lower supply voltages may not be able to operate over a wide common mode input range.